CLS (Cumulative Layout Shift)
Sitecheck Team
A measure of how much unexpected layout shift occurs while a page loads.
CLS (Cumulative Layout Shift) measures how much visible content shifts unexpectedly while a page is loading. Lower CLS means a more stable, less frustrating experience.
Why it matters: Layout shifts can lead to misclicks and a poor user experience; CLS is a Core Web Vitals metric.
Quick tips:
- Reserve space for images and ads with explicit dimensions.
- Avoid inserting content above existing content without user interaction.
- Use font-display and preloading to reduce font shifts.
See also: Core Web Vitals, LCP, INP.